watanabei angelfish are my favorite, very reef safe and active, kind of hard to find though, but most genicanthus angels should be reef safe and most are very beautiful
Here is my male watanabei angel. I've had him for over a year now and have never seen him nip at any corals. As organism said, any of the Genicanthus angels are reef safe, of which the watanabei is one. Others include the Japanese Swallowtail, Lamarck's, Bellus, etc. Many of the pygmy angels are actually not reef safe.
I have a flame angel. If he doesnt stay fed, I see him nip at corals. He doesnt ever "tear" a piece off, just sort of kisses it and goes on his way. He seems to do this more to my open brain than anything else.
I am considering removing him....Its a little scary.